Re-land "fix #30462, update function_type tests to understand covariant generics"

tests/language_2/function_type/function_type96_test.dart

Index: tests/language_2/function_type/function_type96_test.dart
diff --git a/tests/language_2/function_type/function_type96_test.dart b/tests/language_2/function_type/function_type96_test.dart
index 17f3b386870486c2c1f6d47b29c18f072ffaa57b..4c668a1b9470fe3d9f0d36831f33e338b2f8c8a4 100644
--- a/tests/language_2/function_type/function_type96_test.dart
+++ b/tests/language_2/function_type/function_type96_test.dart
@@ -265,10 +265,10 @@ class U96<T> {
       });
     }
     if (tIsInt || tIsBool) {
-      Expect.equals(tIsInt, m3 is F3<int>);
-      Expect.equals(tIsBool, m3 is F3<bool>);
-      Expect.equals(tIsInt, confuse(m3) is F3<int>);
-      Expect.equals(tIsBool, confuse(m3) is F3<bool>);
+      Expect.equals(true, m3 is F3<int>);
+      Expect.equals(true, m3 is F3<bool>);
+      Expect.equals(true, confuse(m3) is F3<int>);
+      Expect.equals(true, confuse(m3) is F3<bool>);
     }
   }